class Book:
    def __init__(self, title, author):
        self.title = title
        self.author = author

class Library:
    def __init__(self):
        self.books = []

    def add_book(self, title, author):
        new_book = Book(title, author)
        self.books.append(new_book)
        print(f"Book '{new_book.title}' by {new_book.author} 被添加到图书馆.")

    def remove_book(self, title):
        for book in self.books:
            if book.title == title:
                self.books.remove(book)
                print(f"Book '{book.title}' by {book.author} 被从图书馆移除.")
                return

        print(f"Book '{title}' not found in the library.")

    def find_book(self, title):
        for book in self.books:
            if book.title == title:
                print(f"Book '{book.title}' by {book.author} 已找到.")
                return book

        print(f"Book '{title}' not found in the library.")
        return
    
    def list_books(self):
        if not self.books:
            print("No books in the library.")
        else:
            print("Books in the library:")
            for book in self.books:
                print(f"- {book.title} by {book.author}")


if __name__ == "__main__":
    library = Library()
    library.list_books()
    library.add_book("The Great Gatsby", "F. Scott Fitzgerald")
    library.add_book("To Kill a Mockingbird", "Harper Lee")
    library.list_books()
    library.find_book("To Kill a Mockingbird")
    library.remove_book("To Kill a Mockingbird")
    library.list_books()
    library.find_book("To Kill a Mockingbird")
    library.remove_book("To Kill a Mockingbird")
    library.list_books()
    library.remove_book("The Great Gatsby")
    library.list_books()
    print("Done.")
